Electron microscope image of the microbe, Geobacter sulfurreducens

The U.S.’s  Naval Research Laboratory  powers mini robots with microorganisms

All sorts of robots are used to help us explore outer space but bigger isn’t always better when it comes to extraterrestrial explorers. These machines require loads of energy and last time we checked, outer space lacks electrical outlets….

Many existing robots used in space, such as the Mars-dwelling Opportunity rover, rely on energy in the form of heat given off from the decay of a radioactive isotope, like Plutonium. While this provides the robot with enough energy to run for over 600 days, at over 900 kg, Opportunity is not exactly a slim and slender bot.

The NRL’s Spacecraft Engineering Department has recently developed an autonomous microrover powered by microbial fuel cell (MFC) technology. “The goal is to demonstrate a more efficient and reliable energy source for use in powering small robotic vehicles in environments where the option for human intervention is non-existent” explains  Gregory P. Scott in an NRL press release.

MFCs  generate electricity from the metabolic processes of bacteria. Bacteria such as  Geobacter sulfurreducens, which doesn’t require oxygen to survive, can be densely packed into a battery where it easily reproduces, allowing  the battery to keep itself charged.

Scott maintains that “As we move forward in the utilization of MFCs as an energy generation method, this research begins to lay the groundwork for low powered electronics with a long-term potential for space and robotic applications.¨